Abstract: A mixture of CFC-113 and CFC-123 and/or CFC-123a where CFC-123 or CFC-123a is a significant portion of the total composition has been found to result in improved blowing agent performance in phenol-formaldehyde foams compared to CFC-113.The use of CFC-123 (or CFC-123a, or both), in combination with CFC-113 improves resole resin solubility and mixed ingredient solution stability, prior to foaming. In addition, because of the lower molecular weight of CFC-123 (or CFC-123a) compared to CFC-113 better blowing agent efficiency will be realized per unit weight. Also, the lower boiling points of CFC-123 and CFC-123a as compared to CFC-113 results in a more ready conversion of dissolved blowing agent to released gaseous blowing agent by the exothermic phenolic resin polymerization. And because of the lower molecular weight and lower boiling point factors, a lower density foam is realized.

Abstract: A mixture of CFC-113 and CFC-123 and/or CFC-123a where CFC-123 or CFC-123a is a significant portion of the total composition has been found to result in improved blowing agent performance in phenol-formaldehyde foams compared to CFC-113.The use of CFC-123 (or CFC-123a, or both), in combination with CFC-113 improves resole resin solubility and mixed ingredient solution stability, prior to foaming. In addition, because of the lower molecular weight of CFC-123 (or CFC-123a) compared to CFC-113 better blowing agent efficiency will be realized per unit weight. Also, the lower boiling points of CFC-123 and CFC-123a as compared to CFC-113 results in a more ready conversion of dissolved blowing agent to released gaseous blowing agent by the exothermic phenolic resin polymerization. And because of the lower molecular weight and lower boiling point factors, a lower density foam is realized.

Abstract: Improved fluorocarbon blowing agents composed of blends of (a) CFC-11, trichlorofluoromethane, with (b) CFC-123 or CFC-123a, dichlorotrifluoroethane, have been found which impart significant improvement in the solubility characteristics of rigid urethane foam systems that contain significant amounts of aromatic polyester polyols. A substantial increase in the solubility of the CFC-11/CFC-123 or CFC-11/CFC-123a blends over CFC-11 alone in typical rigid urethane foam premix systems containing variable concentrations or aromatic polyester polyol is obtained. Preparation of rigid urethane foams have shown that improved solubility CFC-11 blends with CFC-123 or CFC-123a permit an increase in the amount of aromatic polyester polyol than can be used in the formulation without any significant differences in the physical characteristics of foams compared to those produced from CFC-11 without inclusion of aromatic polyester polyols.